Telephone calling or signaling device.



No. 853,389. YPATEANIED MAY '14, 1907. WBMAN,

TELEPHONE CALLING SIGNALING DEVICE.

- nwmoumx FILED DEO.'20. 1905.

wmv5ss5s v INVENTOI? /Q./ZW4 v, meal/mm" 1 72.7 8M4 ATTORN Y UNITED STATES- KLAS or BUFFALO, NEW YORK.

TELEPHONE CALLING OH SIGNALING DEVICE.

Specification of Letters Patent.

Patented May 14, 1907.

Application filed December 20, 1905. Serial No. 292.595.

To a, whom, 1J1; Tnay concern:

Be it known that L'KLAS W EMAN, a subject of the'King of Sweden, residing at Buffalo, New York, have invented certain new and useful Improvements in Telephone Calling or Signaling Devices, of which the following is a specification.

My invention relates to telephone calling or sig'i'laling devices as generally employed in central exchanges, and is particularly applicable to party line systems.

The object of the invention is to provide a signal which is unresponsive 'to any currents except continuous or intermittent currents having a polarity opposite to that of the calling device itself.

In the accompanying drawing, presenting a side elevational view, I have shownthe preferred embodiment of my invention.

Referring to the drawing, 1 represents a soft ironcore, about which two windings, 2 and 3, are arranged, the former being short circuited, and the terminals of the latter bee i'ng connected to binding posts or the like 4 and 5. At the forward end of the core 1, and formed, preferably, integrally therewith, is

an enlarged soft iron head 6, to which a nonmagnetic yoke 7 is suitably secured. 8 and 9 designate non-magnetic collars carried by the core 1 to prevent the windings 2 and 3 from being displaced thereon.

Suitably pivoted to the yoke 7 is a' drop or shutter 10, which has an aperture 1 1, through which the latch end 12 of a permanent magnet armature 13 projects. The yoke 7 is provided with a similar aperture to permit the projection of the end of the armature 13 therethrough. At its rear end 14, the armature 13 is cut out to present a substantial V- shaped face, and is adapted to receive the tapered point 15, of a soft iron bar 16, bent downwardly to form a portion 17, which, by means of a soft iron screw 18, is firmly secured to the core 1. For practical purposes the bar 16 may be considered an extension of the'armature 13.

Projecting upwardly from the core 1, and

heldthereon by the screw 18, is a bracket 19,

which supports a rod 20. Atone end the rod 20 is screw threaded and is provided with a knurled nut 21, between which and the bracket 19 a spiral spring is interposed (22).

23 designates suitable washers at each side of the SPIlH '22. The opposite end of the rod 20 is forme into a joint 24., in which a short rod 25, is held, the rod 2-5 being secured to one face of the armature by-a pin or the'like 26. It will be understood that by turning the nut 21 the tension between armature 13 and bar 16 may be regulated.

The following examples will serve to illustrate the operation of the invention, and. show its underlying principle Assuming that a continuous positive current enters either at post 4 or 5, the current will flow through winding 3, magnetize core 1, and. produce, say, a south pole at head 6. An induced current will be momentarily set up in coil 2, which will tend to retard the pro duction of the south pole at 6, but this tendency will be overcome by the steady flow of current through winding 3. Assuming, further, that the latch end of armature 13 is a north pole, the armature 13 will be attracted to the head. 6, when a south pole there manifests itself, thus releasing the latch 12 and allowing the shutter 10 to fall and give the signal. If a continuous negative current were to flow through winding 3, a north pole would appear at 6, thus repelling the end 12' and permitting the armature 13 'to remain current to enter the winding 3, the head 6 would have a south polarity, which there would be a tendency to retard by a momentarily induced currentin winding 2. The sudden cessation of the impulses of the intermittent current would produce in winding 2 a current that would tend to intensify the south pole at 6,. thus increasing its attractive force for the armature, which, when descending, would release the shutter and give the signal. An intermittent negative current flowing through winding 3 would produce a north polarity at head 6 and. thus Assuming an alternating current to enter the winding 3, the core 1 would be magnetized, and the polarity of its ends would vary with the variations in the direction of the current impulses. As the influence of-the head 6 on the armature 13 is strongest upon cessation of a positive impulse, it is obvious, that a negative impulse, following immediately upon a positive impulse, would neutralize the latter, and there being a certain amount armature would not be attracted, and no signal would be given.

It is to be understood that my invention is not limited to the details herein illustrated and described, and that the invention is sus stationary. Were an intermittent positive.

the latter would not attract the armature 13.

of inertia of the armature to overcome, the

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'. collar, one of said helices having its terminals joined and the other helix having terminals adapted for connection with a source of electrio current, a soft iron bar firmly secured to said core, a permanent magnet armature loosely contacting with said bar and a jointed rod connected to said armature and adapted to hold the same in contact with said soft iron bar.

2. In a device of the character described, the combination of a core, two helices wound thereabout and spaced from each/other, one helix having its terminals joined and the other helix having ends adapted for connection with a source of electricity, a shutter associated with one end of said core, a permanent magnet armature adapted to engage said shutter, a soft iron bar mounted upon saidcore and reaching into engagement with said armature, and a jointed rod secured to said armature and ada ted to hold the same in contact with said. so t iron bar.

3. In a device of the character described, the combination of a core, two helices wound thereabout, a collar upon the core for separating the helices, an angular soft iron bar secured to the core and having an arm extending longitudinally over one said helix, a permanent magnet armature lying over the other helix and being adapted to engage said arm, a bracket projecting from said core, and a jointed rod secured to said armature and being supported by said bracket, said jointed rod being adapted to hold the armature in contact with the arm of said soft iron bar.

4. In a device of the character described, the combination of acore carrying two helices, a soft iron bar having an arm extending parallel over one helix, and apermanent magnet armature lying over the other helix and engaging said arm and means for regulating the-intimacy of contact between said armature and. arm, said means comprising a bracket supporting a jointed rod secured to said armature, and a helical spring surrounding a portion of said rod.

5. In a telephone signaling device responsive only to direct electric current, the combinationof a core having a shutter pivoted near one end thereof, a single permanent magnet armature associated with said core and normally engaging said shutter, an angular soft iron bar mounted upon said core, and being in engagement with said armature, means for regulating the intimacy of contact between said armature and bar, thereby regu lating the tension of said armature, a helix,

whose ends are joined, wound about said iron bar extending upwardly from the core and having a horizontal arm engaging said armature, means for regulating the intimacy of contact between the armature and arm thereby regulating the tension of said armature, and a second helix wound about said core, having terminals adapted for connection with a source of electricity.

7. In a device of the character described, the combination of a soft'iron core provided with an enlarged head at one end, a collar intermediate its length and a second collar at its opposite end, two helices arranged suc cessively upon said core and being separated by said intermediate collar, one of said helices having its ends joined together, a yoke associated with said head, a shutter pivoted at the lower part of said yoke, a two part armat-ure arranged over said core, the forward part of said armature having a latch adapted to engage said shutter and means for regulating the degree of contact between the parts of said armature, said means comprising a jointed rod held in a bracket projecting upwardly from thecore.

In testimony whereof I have affixed my signature in presence of two witnesses.

KLAS WEMAN. 

